The 83X Mid Market Express bus is seen on 9th St. and Market in San Francisco, CA Thursday August 9th, 2012

The 83X Mid Market Express bus is seen on 9th St. and Market in San Francisco, CA Thursday August 9th, 2012

Photo: Michael Short, Special To The Chronicle

Image 6 of 9

The MUNI sign for the 83X Mid Market Express in San Francisco, CA Thursday August 9th, 2012

The MUNI sign for the 83X Mid Market Express in San Francisco, CA Thursday August 9th, 2012

Photo: Michael Short, Special To The Chronicle

Image 7 of 9

The 83X Mid Market Express bus is seen at 9th and Market with the Twitter office in the background in San Francisco, CA Thursday August 9th, 2012

The 83X Mid Market Express bus is seen at 9th and Market with the Twitter office in the background in San Francisco, CA Thursday August 9th, 2012

Photo: Michael Short, Special To The Chronicle

Image 8 of 9

People board the 83X Mid Market Express bus as it makes a stop on 9th and Market St.'s in San Francisco, CA Thursday August 9th, 2012

People board the 83X Mid Market Express bus as it makes a stop on 9th and Market St.'s in San Francisco, CA Thursday August 9th, 2012

Photo: Michael Short, Special To The Chronicle

Image 9 of 9

Muni's Twitterbus off to a slow start

1 / 9

Back to Gallery

Ridership on Muni's newest route, informally known as the Twitterbus, so far is nothing to tweet about, though transit officials expect that to change as the long-dormant Mid-Market area begins to boom.

But the 83X-Mid-Market Express, begun in mid-June to serve the new Twitter headquarters and the other tech businesses arriving soon, will face some stiff, and until now, unknown, competition: a private shuttle.

Shorenstein Realty Services, which owns the 1937 Art Deco building that housed the Western Furniture Exchange and Merchandise Mart and is now home to Twitter, plans to begin running a free employee shuttle between its building and the Caltrain station, a virtual replication of the 83X route. It could start running before the end of the year.

"Unbeknownst to us, the city decided to put the bus into place," said Jim Collins, Shorenstein vice president for leasing. "We felt there was a need to put a direct connection to Caltrain in place, so we set up a shuttle. Had we known the city was going to start the (express) bus, we probably wouldn't have needed to do that."

Pact for private shuttle

Collins said Shorenstein is obligated by an agreement to start running the shuttle when One Kings Lane, a home decor website, moves into the building, possibly by the end of this year. Call center company CallSocket and social-networking service Yammer are also expected to move in this year or in early 2013, and Shorenstein is seeking tenants for a smaller adjoining building.

Use of the shuttle will be restricted to workers at Market Square, the name for the almost 1.1 million-square-foot Shorenstein development at 1355 Market St., which will also feature ground-floor retail. But that means up to 5,000 potential Muni passengers will be offered free shuttle rides.

Paul Rose, a Municipal Transportation Agency spokesman, said officials were not aware of the shuttle plans and apparently hadn't discussed the 83X with developers before starting the service. But he said the agency is still optimistic that the new express line will catch on.

"The fact that companies are willing to use their resources to provide employee shuttles proves that this service is needed," he said. The Municipal Transportation Agency created the 83X at the same time it was wrestling with an $18.6 million budget deficit over the next two years. The agency filled the budget hole in large part by hiring additional enforcement officers to write more tickets and crack down on illegal taxis.

Twitter headquarters, which opened in mid-June, is credited with leading the rebirth of a business district long in decline. City officials used a combination of loans, grants and a controversial tax break to keep Twitter in San Francisco and to lure new businesses and construction. Muni said the bus service was needed to link Caltrain with the growing business district.

Besides the Market Square tenants, the audio technology firm Dolby Laboratories recently announced plans to move into a building at Ninth and Market streets near Twitter headquarters. The company expects to bring 700 to 1,000 employees to the neighborhood.

Two major residential developments - 750-unit Crescent Heights and 273-unit AvalonBay - are being built on opposite sides of Market Square.

"We're just at the very, very start," said Tom McDonnell, a Shorenstein vice president for leasing, referring to the growth of Mid-Market. "We've got a lot of time in front of us to get that bus filled."

Underperforming line

Muni officials hope so. The 83X is underperforming. In its first month and a half of service, the commute-hours-only route has hauled an average of just 343 passengers a day - about six or seven per run. At that rate, ridership would total about 87,000 a year, far short of the 400,000 annual trips the express bus was projected to carry.

"These types of numbers are expected when you start a new line," Rose said. "When people learn about the service, and when new residents and businesses move in, (ridership) will grow."

Most of the 83X riders are employees bound for Twitter's new headquarters on Market Street between Ninth and 10th streets. On a recent morning, six of the seven employees aboard the bus were Twitter employees. While the 83X isn't always lined up perfectly with Caltrain's arrival, they said the bus is much faster than taking other Muni buses or walking.

"It's pretty convenient," said Aaron Lewis, a Twitter engineering intern who takes Caltrain from Mountain View then rides the 83X. "There's a little bit of waiting, but it gets you back and forth."

Rose said Muni officials expect ridership to increase in the fall as summer vacation season ends and more people become aware of the route. The agency is considering adding a fourth stop at Townsend and Brannan streets to serve Zynga, Adobe, Advent and other employers. Each month Muni will monitor the service, review the ridership and make adjustments as needed, Rose said.

Latest from the SFGATE homepage:

Click below for the top news from around the Bay Area and beyond. Sign up for our newsletters to be the first to learn about breaking news and more. Go to 'Sign In' and 'Manage Profile' at the top of the page.